Poro was talking a walk with his owner, the Protagonist, in the road near the tunnel. As it was starting to get dark soon, his she decided to return home. As they walked back, a Hand Spirit ran pass behind them. But despite sensing it, they weren't able to see it and thought it was just their imagination. They then continues to walk. Suddenly, a Pebble fell from above a wall next to the road, so the girl decided to play a moment of fetch with Poro by using the pebble. However, as Poro was about to retrieve the thrown pebble, a truck came out of nowhere and accidentally ran over the dog. Poro was instantly killed, as his blood splattered the road and his body was sent over the cliff & into the deepest parts of the Mountains. As Poro dies, he becomes a Spirit.

As a Spirit, Poro left his body and the Mountains. As he wandered through Town, he encounters his owner, the Protagonist. He ended up leading her to his body. The girl tries to wake his body up, but she was eventually forced to realize and accept that Poro had died. Crying, the girl couldn't help but blame herself for what happened to Poro and blame herself for getting her sister in this situation by not telling her what really happened. She then buries Poro's body there and places a stone grave with flowers. She was forced to leave, accepting that Poro was gone. However, before leaving the Mountains, she runs into a ghost train and finds the Torn Collar of Poro.

After the Protagonist saved her sister from the Mountain Spirit and loses her eye as a result, she loses consciousness. During her unconsciousness, she finds herself in the Limbo World where Poro was waiting. Poro was about to enter the tunnel to go to the afterlife. So the Protagonist bids Poro goodbye before leaving to return to the living world. Poro then enters the tunnel, and into the afterlife.

The next day, the Protagonist, wearing an Eyepatch over her missing left eye, visits Poro's grave with her sister and left the dog some flowers. The two then returned home.